Vascular remodeling device

ABSTRACT

A generally spherical vascular remodeling device is permanently positionable at a junction of afferent and efferent vessels of a bifurcation having an aneurysm. After positioning the device at the junction to substantially conform the device to the shape of the junction, the device acts as a scaffolding to inhibit herniation of objects out of the aneurysm and permits perfusion to the efferent vessels. Positioning the device may include deployment and mechanical or electrolytic release from a catheter. Embolic material may be inserted in the aneurysm before or after positioning the device. The device may have a first end, a second end substantially opposite to the first end, and a plurality of polymer filaments extending between and coupled at the first end and the second end. Such devices may be football shaped, pumpkin shaped, or twisted. The device may include a plurality of polymer loops forming a generally spherical shape.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. application Ser. No.13/016,858, filed Jan. 28, 2011, which claims priority benefit of U.S.Provisional Patent Application No. 61/299,266, filed Jan. 28, 2010,which is incorporated herein by reference in its entirety.

BACKGROUND

1. Field

The present application generally relates to vascular remodeling devicesand to the manner of their positioning in vessels, and, moreparticularly, to generally spherical remodeling devices and to thematter of their positioning at the junction of neurovascularbifurcations having an aneurysm.

2. Description of Related Art

Neurovascular or cerebral aneurysms affect about 5% of the population.Aneurysms may be located, for example, along arterial side walls (e.g.,the aneurysm 10 illustrated in FIG. 1) and at arterial bifurcations(e.g., the aneurysm 20 illustrated in FIG. 2). The direction of fluidflow is generally indicated by the arrows 16, 26. The aneurysms 10, 20each have a fundus 12, 22, a neck 14, 24, and a fundus-to-neck ratio or“neck ratio.” If the neck ratio is greater than 2 to 1 or if the neck14, 24 is less than 4 mm, the aneurysm 10, may be treated withembolization coils alone because the coils will generally constrainthemselves within the aneurysm 10, 20 without herniating into parentvessels. If the neck ratio is less than 2 to 1 or if the neck 14, 24 isgreater than 4 mm, the aneurysms 10, 20 may be difficult to treat withembolization coils alone because the coils may be prone to herniatinginto parent vessels, as illustrated in FIGS. 3A and 3B. Herniation ofcoils may cause arterial occlusion, stroke, and/or death. Compared tothe bifurcation illustrated in FIG. 2, the efferent vessels of thebifurcation may be at substantially different angles, have substantiallydifferent sizes, and/or be a different quantity (e.g., three or more).Compared to the bifurcation illustrated in FIG. 2, the aneurysm 20 ofthe bifurcation may be offset with respect to the junction (e.g., havinga neck substantially open to one efferent vessel), tilted with respectto a plane created by the vessels (e.g., into or out of the page), etc.Each of these would still be accurately characterized as a “bifurcation”herein.

In order to inhibit such herniation, tubular neck remodeling devices,for example Neuroform™, available from Boston Scientific, andEnterprise™, available from Cordis Neurovascular, may be used to keepcoils or other materials within the fundus of the aneurysm and out ofthe vessels. Tubular remodeling devices generally consist of a braidedwire or cut metallic stent or stents covering the neck of the aneurysmso that materials introduced into the fundus of the aneurysm do notherniate out of the aneurysm. As illustrated in FIG. 4A, tubularremodeling devices 40 are generally useful for side wall aneurysms 10.As illustrated in FIGS. 4B and 4C, tubular remodeling devices 42, 44 aregenerally less useful for aneurysms 20 at bifurcations, for examplebecause shaping the remodeling devices to preserve blood flow throughthe afferent and efferent vessels while also inhibiting herniation ofcoils 28 out of the aneurysm 20 can be difficult.

SUMMARY

In some embodiments described herein, a generally spherical vascularremodeling device is provided. The device is permanently positionable ata junction of afferent and efferent vessels of a bifurcation (e.g., aneurovascular bifurcation) having an aneurysm having a fundus and aneck. Positioning may comprise deployment from a catheter and mechanicalor electrolytic release from the catheter. After positioning the deviceat the junction, the device can lock into place across the arterialostia and the neck of the aneurysm, substantially conforming to theshape of the junction. After positioning the device at the junction, thedevice acts as a scaffolding to inhibit or prevent herniation orprolapse of objects such as embolization coils and thrombi out of theneck of the aneurysm. Embolic material may be inserted in the fundus ofthe aneurysm before or after positioning the device. After positioningthe device at the junction, the device permits perfusion of fluid (e.g.,blood) to the efferent vessels. The device may have a first end, asecond end substantially opposite to the first end, and a plurality ofpolymer filaments extending between and coupled at the first end and thesecond end. Certain such devices may be football shaped, pumpkin shaped,or twisted. The polymer filaments may comprise bioabsorbable polymers(e.g., polylactic acid, polyglycolic acid, poly(lactic-co-glycolicacid), poly-epsilon-caprolactone, and/or naturally-derived bioabsorbablepolymers). The device may comprise a plurality of loops (e.g., circularloops) or filaments forming a generally spherical shape, each loopcomprising a bioabsorbable polymer (e.g., polylactic acid, polyglycolicacid, poly(lactic-co-glycolic acid), poly-epsilon-caprolactone, and/ornaturally-derived bioabsorbable polymers). Radiopaque markers may beplaced at one or both ends of the device and/or at least one of theloops or filaments may comprise a radiopaque material (e.g., platinum).In certain embodiments, a method of treating an aneurysm at a junctionof a bifurcation having an afferent vessel and efferent vessels isprovided. The aneurysm has a neck and a fundus. The method comprisesadvancing a catheter proximate to the junction of the bifurcation. Thecatheter at least partially contains a generally spherical vascularremodeling device in a compressed state. The device comprises aplurality of polymer filaments. The method further comprises positioningthe device at the junction of the bifurcation and withdrawing thecatheter and leaving the device at the junction of the bifurcation. Thedevice acts as a scaffolding to inhibit herniation of objects out of theneck of the aneurysm after withdrawal of the delivery catheter. Thedevice permits perfusion of fluid to the efferent vessels.

In certain embodiments, a generally spherical remodeling devicecomprises a first end, a second end substantially opposite to the firstend, and a plurality of polymer filaments extending between the firstend and the second end and coupled at the first end and the second end.The device is configured to be positioned at a junction of a bifurcationcomprising at least one afferent vessel, efferent vessels, and ananeurysm having a neck after withdrawal of a delivery catheter. Thedevice is configured to act as a scaffolding to inhibit herniation ofobjects out of the neck of the aneurysm. The device is configured topermit perfusion of fluid to the efferent vessels.

In certain embodiments, a remodeling device comprising a plurality ofpolymer arcuate loops forming a generally spherical shape is provided.The device is configured to be positioned at a junction of a bifurcationhaving an aneurysm after withdrawal of a delivery catheter. The deviceis configured to act as a scaffolding to inhibit matter from herniatingout of the aneurysm. The device is configured to permit perfusion ofblood to efferent vessels of the bifurcation.

For purposes of summarizing the invention and the advantages achievedover the prior art, certain objects and advantages of the invention aredescribed herein. Of course, it is to be understood that not necessarilyall such objects or advantages need to be achieved in accordance withany particular embodiment. Thus, for example, those skilled in the artwill recognize that the invention may be embodied or carried out in amanner that achieves or optimizes one advantage or group of advantagesas taught or suggested herein without necessarily achieving otherobjects or advantages as may be taught or suggested herein.

All of these embodiments are intended to be within the scope of theinvention herein disclosed. These and other embodiments will becomereadily apparent to those skilled in the art from the following detaileddescription having reference to the attached figures, the invention notbeing limited to any particular disclosed embodiment(s).

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects, and advantages of the presentdisclosure are described with reference to the drawings of certainembodiments, which are intended to illustrate certain embodiments andnot to limit the invention.

FIG. 1 illustrates an example embodiment of a side wall aneurysm.

FIG. 2 illustrates an example embodiment of a bifurcation having ananeurysm.

FIG. 3A illustrates an example embodiment of a side wall aneurysm withherniating embolization coils.

FIG. 3B illustrates an example embodiment of a bifurcation having ananeurysm with herniating embolization coils.

FIG. 4A illustrates an example embodiment of a side wall aneurysmtreated with embolization coils and a tubular remodeling device.

FIGS. 4B and 4C illustrates example embodiments of a bifurcation havingan aneurysm treated with embolization coils and tubular remodelingdevices.

FIG. 5 illustrates an example embodiment of a generally sphericalvascular remodeling device.

FIGS. 6A-6C illustrate an example embodiment of a method for treating ananeurysm using the device of FIG. 5.

FIGS. 7A-7C illustrate another example embodiment of a method fortreating an aneurysm using the device of FIG. 5.

FIG. 8 illustrates another example embodiment of a generally sphericalvascular remodeling device.

FIGS. 9A-9C illustrate an example embodiment of a method for treating ananeurysm using the device of FIG. 8.

FIGS. 10A-10C illustrate another example embodiment of a method fortreating an aneurysm using the device of FIG. 8.

FIG. 11 illustrates yet another example embodiment of a generallyspherical vascular remodeling device.

FIG. 12 illustrates an example embodiment of treating an aneurysm usingthe device of FIG. 11.

FIG. 13 illustrates still another example embodiment of a generallyspherical vascular remodeling device.

FIG. 14 illustrates an example embodiment of a generally sphericalvascular remodeling device at a stage of an example manufacturingprocess.

DETAILED DESCRIPTION

Although certain embodiments and examples are described below, those ofskill in the art will appreciate that the invention extends beyond thespecifically disclosed embodiments and/or uses and obvious modificationsand equivalents thereof. Thus, it is intended that the scope of theinvention herein disclosed should not be limited by any particularembodiments described below.

FIG. 5 illustrates an example embodiment of a generally sphericalvascular remodeling device 50. It will be appreciated that the device 50may be more compliant than the vasculature in which it is deployed suchthat it may be somewhat misshapen (e.g., non-spherical, for example asillustrated in FIG. 6B) after being deployed, and that the phrase“generally spherical” describes the shape of the device 50 when in anexpanded (e.g., fully expanded) state. Additionally, the phrase“generally spherical” distinguishes the device 50, which is generallyuniform in each dimension in an expanded state, from tubular stentshaving a small radial dimension and a large longitudinal dimension in anexpanded state. In some embodiments of a generally spherical device, anouter periphery of the device has a shape that deviates by between about10% and about 25% from an outer periphery of a mathematically perfectsphere. In some embodiments, the device 50 has a length and a width thatare within less than about 33% of each other (e.g., having a length of 6mm and a width of 8 mm, having a length of 6 mm and a width of 8 mm).Embodiments in which the width is greater than the length may beadvantageous due to a difference in porosity at a midpoint and an endproximate to an aneurysm. Embodiments in which the length is greaterthan the width may be advantageous for positioning a portion of thedevice 50 in a portion of the aneurysm 20 (e.g., to aid inembolization).

In the embodiment illustrated in FIG. 5, the device 50 comprises aplurality of generally circular loops 52 coupled together. Coupling ofthe loops 52 may comprise adhering, welding, soldering, interlacing(e.g., some loops 52 being over or under other loops 52), intertwining,meshing, combinations thereof, and the like. In the embodimentillustrated in FIG. 5, the device 50 comprises a lead or tail 53, whichmay be used for releasing and/or retracting the device 50 afterdeployment, as described herein. In some embodiments, the device 50comprises a cut metallic sphere, a single filament, a plurality ofnon-circular filaments (e.g., arcuate segments), etc. In someembodiments, each loop 52 forms a plane and the intersections of theplanes are substantially parallel (e.g., as illustrated in FIG. 7A).

In some embodiments, at least some of the loops 52 or filaments comprisea self-expanding and/or a shape-memory material (e.g., comprisingNitinol, CoCr alloy, etc.), thereby causing the device 50 to beself-expanding under certain conditions (e.g., not restrained by acatheter). In some embodiments, at least one of the loops 52 comprises adifferent material than others of the loops 52 (e.g., some loops 52comprising Nitinol and some loops 52 comprising Nitinol and platinum).In some embodiments, at least one of the loops 52 comprises a radiopaquematerial (e.g., platinum). In certain such embodiments, an even numberof loops 52 (e.g., two, four, etc.) comprises a radiopaque material(e.g., platinum). In some embodiments, at least one of the loops 52comprises a radiopaque material (e.g., platinum) at least partiallywrapped (e.g., coiled) around a self-expanding material (e.g., Nitinol).In some embodiments, at least one of the loops 52 comprises aself-expanding material with a radiopaque core (e.g., Nitinol with aplatinum core) or a radiopaque coating (e.g., Nitinol coated withplatinum, tantalum, etc. by physical vapor deposition, chemical vapordeposition, plating, etc.). It will be appreciated that the amount andtype of radiopaque material used may depend, inter alia, on price,desired level of radiopacity, mechanical properties of the radiopaquematerial, and corrosion properties of the radiopaque material. Incertain embodiments, the loops 52 have a substantially circular or ovoidcross section (e.g., embodiments, in which the loops 52 compriseseparate wires). In some embodiments, the loops 52 have a substantiallyrectangular or flat cross section (e.g., embodiments, in which the loops52 comprise uncut portions of a metallic tube). Other shapes of loops 52and combinations of shapes of loops 52 are also possible. In certainembodiments, the plurality of loops 52 comprises between about six andabout twelve loops 52. In certain embodiments, the plurality of loops 52comprises at least about six loops 52, at least about eight loops 52, orat least about twelve loops 52. Other numbers of loops 52 are alsopossible.

In certain embodiments, at least some of the loops 52 or filamentscomprise a polymer. In some embodiments, at least some of the loops 52or filaments comprise a polymer that is bioabsorbable. In certainembodiments, at least some of the loops 52 or filaments comprisepolyglycolic acid (PGA), polylactic acid (PLA), poly(lactic-co-glycolicacid) (PLGA), poly-epsilon-caprolactone (PCL), naturally-derivedbioabsorbable polymers (NDB), or combinations thereof (e.g., a firstgroup of the loops 52 comprising PGA and a second group of the loops 52comprising PLA, PLGA, PCL, and/or NDB, a first group of the loops 52comprising PLA and a second group of the loops 52 comprising PGA, PLGA,PCL, and/or NDB, a first group of the loops 52 comprising PLGA and asecond group of the loops 52 comprising PLA, PGA, PCL, and/or NDB, afirst group of the loops 52 comprising PCL and a second group of theloops 52 comprising PGA, PLA, PLGA, and/or NDB, a first group of theloops 52 comprising NDB and a second group of the loops 52 comprisingPGA, PLA, PLGA, and/or PCL, etc.). Other polymers are also possible.PGA, PLA, PLGA, PCL, and NDB are all bioabsorbable; however they havedifferent rates of bioabsorption. The bioabsorption rates of a singlepolymer can also vary based on, for example, blood characteristics,blood flow, loop 52 dimensions, etc. PLA has the longest bioabsorptionrate. In some embodiments, the bioabsorption rate of PLA is at leastabout ten months. In some embodiments, the bioabsorption rate of PLA isat least about one year. In some embodiments, the bioabsorption rate ofPLA is at least about fourteen months. In some embodiments, thebioabsorption rate of PLA is between about 10 months and about 14 months(e.g., about one year). In some embodiments, the bioabsorption rate ofPGA is between about 1 week and about 3 weeks. In some embodiments, thebioabsorption rate of PGA is between about 2 weeks and about 4 weeks.The bioabsorption rates of PLGA, PCL, and NDB are generally between thebioabsorption rates of PLA and PGA, and may depend on parameters suchas, for example, molecular weight (e.g., generally the higher themolecular weight, the longer the bioabsorption rate), structure (e.g.,depending on the arrangement of repeating units), etc. of the polymer.In some embodiments, PLGA, PCL, and NDB may have a bioabsorption ratebetween about 4 weeks and about 1 year. The bioabsorption rate generallyrefers to the time lose about 50% of strength. The polymer(s) used inthe device 50 may be selected based on the amount of time an aneurysmmay take to thrombose (e.g., based on fundus size, neck width, etc.).For example, if an aneurysm is expected to take one month to thromboseand the device 50 is expected to persist through thrombosis but not longthereafter, PGA may be selected. The polymer(s) used in the device 50may be selected based on the amount of time an aneurysm may take toobliterate (e.g., based on fundus size, neck width, etc.). For example,if an aneurysm is expected to take one year to obliterate and the device50 is expected to persist through obliteration, PLA may be selected.Other polymers or combinations of polymers can be selected based on theparticular aneurysm to be treated and the desired action and/orpersistence of the device 50 with respect to the aneurysm. Otherselection criteria are also possible. Different combinations of polymerswith different rates of bioabsorption can allow for selection of adesired rate of bioabsorption for the device 50. For example, a device50 with a combination of PGA and PLA loops 52 may have a rate ofbioabsorption in between the rate of bioabsorption of a device 50comprising only loops 52 comprising PGA and the rate of bioabsorption ofa device 50 comprising only loops 52 comprising PLA.

In certain embodiments, the device 50 is configured to be positioned ata junction of a bifurcation (e.g., a neurovascular bifurcation)comprising at least one afferent vessel, efferent vessels, and ananeurysm having a fundus and a neck. For example, in some embodiments,the device 50 is suitably dimensioned to fit in a junction of abifurcation (e.g., having a diameter between about 2 mm and about 12 mm,having a diameter between about 6 mm and about 8 mm, having a diameterless than about 12 mm, having a diameter greater than about 2 mm). Foranother example, in some embodiments, the device 50 is less rigid than ajunction of a bifurcation (e.g., due to the number of loops 52, thematerial of the loops 52, the thickness of the loops 52, the spacing ofthe loops 52, the shape of the loops 52, combinations thereof, and thelike). In certain embodiments, the device 50 is configured to act as ascaffolding to inhibit or prevent herniation or prolapse of objects(e.g., embolization coils, thrombi, etc.) out of a neck of an aneurysm.For example, in some embodiments, the loops 52 are dense enough at theneck of the aneurysm that objects cannot pass. In certain embodiments,the device 50 is configured to permit perfusion of fluid (e.g., blood)to efferent vessels of a bifurcation. For example, in some embodiments,the device 50 is substantially devoid of a covering, mesh, or othermaterial between the loops 52, thereby allowing fluid to flowsubstantially unimpeded.

The device 50 comprises a plurality of perforations or cells 54 betweenthe loops 52. In certain embodiments, a percentage of the outer surfaceof the device 50 covered by the loops 52 is between about 25% and about40%. In certain embodiments, a percentage of the outer surface of thedevice 50 covered by the cells 54 is between about 60% and about 75%.Other porosities are also possible. In some embodiments (e.g., inembodiments in which the device 50 comprises loops 52 that form a planeand in which the intersections of the planes are substantially parallel(e.g., as illustrated in FIG. 7A)), porosity distally increases betweena proximal end of the device 50 and an approximate midpoint and distallydecreases between the approximate midpoint and a distal end of thedevice 50. In some embodiments, the device 50 further comprises one ormore radiopaque markers (e.g., comprising or at least partially coveringa portion of a loop 52, at a proximal end of the device 50, at a distalend of the device 50, etc.).

FIGS. 6A-6C illustrate an example embodiment of a method for treating ananeurysm 20 using the device 50. FIG. 6A illustrates a confluence ofafferent and efferent vessels or “junction” at a bifurcation 60 havingan aneurysm 20. In some embodiments, the vessels are neurovascular orcranial. The aneurysm 20 is illustrated with a plurality of embolizationcoils 62 having been inserted in the fundus 22 of the aneurysm 20. Itwill be appreciated that the embolization coils 62 may be a singleembolization coil or other embolic material. A catheter 64 (e.g., amicrocatheter), at least partially containing a constricted orcompressed device 50, is also shown in the afferent vessel. The catheter64 is small enough and flexible enough to be routed through thevasculature and situated proximate to the aneurysm 20. In someembodiments, the embolization coils 62 are inserted in the fundus 22 ofthe aneurysm 20 using the catheter 64. In some embodiments, theembolization coils 62 are inserted in the fundus 22 of the aneurysm 20using a different catheter. In certain such embodiments, a guidewire maybe used to guide both catheters.

FIG. 6B illustrates the bifurcation 60 after the device 50 has beendeployed from the catheter 64 (e.g., by being pushed out with a plunger,by retracting the catheter 64 while the device 50 remains stationary,etc.). After being deployed from the catheter 64, the device 50 mayexpand. In some embodiments, the device 50 comprises a self-expandingand/or a shape-memory material that automatically expands towards anuncompressed state or does so upon the application of warm fluid (e.g.,saline). The device 50 may substantially conform to the shape of thejunction of the bifurcation 60 (e.g., not substantially includingportions extending into the afferent and efferent vessels) and locksinto place across the ostia of the afferent and efferent vessels and theneck 24 of the aneurysm 20. The device 50 at least partially covers theneck 24 of the aneurysm 20 as well as the afferent and efferent vessels,but does not need to divert flow. The device 50 acts as a scaffolding toinhibit or prevent herniation or prolapse of objects such as theembolization coils 62 and/or thrombi out of the aneurysm 24. The device50 also allows perfusion of fluid (e.g., blood) from the afferentvessel(s) to the efferent vessel(s).

FIG. 6C illustrates the bifurcation 60 after the device 50 has beenreleased from the catheter 64. In some embodiments, the device 50 isreleased mechanically (e.g., by a release mechanism). In someembodiments, the device 50 is released electrolytically (e.g., byapplying a small current until a portion of the tail 53 proximal to thedevice 50 corrodes away, as illustrated by the gap 65). The catheter 64is then withdrawn from the bifurcation 60, thereby leaving orpermanently positioning the device 50 at the junction of the bifurcation60.

It will be appreciated that the term “permanently” does not mean thatthe device 50 is impossible to remove at a later time. In someembodiments, the device 50 may be retracted into the catheter 64 afterbeing deployed from the catheter 64 (e.g., by pulling on the tail 53).The device 50 may then be deployed, for example at a new angle, at a newrotational position, more proximal or distal to an afferent vesseland/or an efferent vessel, etc. For example, although the device 50expands towards an uncompressed state after deployment, the resultingshape of the device 50 at the junction of the bifurcation 60 may varydepending on the details of the deployment from the catheter 64 becausethe device 50 adapts to the shape of the anatomy (e.g., due to the size,shape, number, etc. of the loops 52). Once the user is satisfied withproperties of the device 50 (e.g., position, tilt, rotation, shape,interaction with the vessels, etc.), the device 50 may be released asdescribed herein.

Combinations of the steps described above are also possible. In someembodiments, the embolization coils 62 may be inserted in the fundus 22of the aneurysm 20 after the device 50 has been deployed from thecatheter 64 (e.g., using the catheter 64 to insert the embolizationcoils 62). In some embodiments, the embolization coils 62 may beinserted in the fundus 22 of the aneurysm 20 after the device 50 hasbeen released from the catheter 64 (e.g., using the catheter 64 toinsert the embolization coils 62).

In certain embodiments, the loops 52 or filaments comprise abioabsorbable polymer. This bioabsorbability can be advantageous inconjunction with permanent placement of the device 50. For example,after thrombosis of the aneurysm following treatment, the device 50 mayno longer be needed to inhibit herniation of material. Certainbioabsorbable embodiments of the device 50 may advantageously inhibitherniation during thrombosis of the aneurysm, but bioabsorb when theymay no longer be needed to inhibit herniation. This can make permanentplacement, or release of the device 50, a less consequential procedureas a device 50 comprising bioabsorbable filaments 52 will not remain inthe vasculature permanently.

FIGS. 7A-7C illustrate another example embodiment of a method fortreating an aneurysm 20 using the device 50. In the method describedwith respect to FIGS. 6A-6C, the device 50 was pre-assembled outside ofthe vasculature prior to positioning. By contrast, in the methoddescribed with respect to FIGS. 7A-7C, the device 50 is introducedpiecemeal and is constructed within the patient at the bifurcation 60.FIG. 7A illustrates a first loop 66 and a second loop 68 positionedacross the neck 24 of the aneurysm 20 and the ostia of the afferent andefferent vessels. In some embodiments, the first loop 66 is positionedand the second loop 68 is then positioned inside the first loop 66. Insome embodiments, a plane defined by the positioned first loop 66 issubstantially perpendicular to the plane of the neck 24 of the aneurysm20 and a plane defined by the positioned second loop 68 is substantiallyperpendicular to the plane of the neck 24 of the aneurysm 20. In certainembodiments, the first loop 66 and the second loop 68 are positioned viadeployment from a same catheter. In certain embodiments, the first loop66 is positioned via deployment from a first catheter, the second loop68 is positioned via deployment from a second catheter, and so on. Insome embodiments, the device 50 is not released from a catheter, buteach loop 52 is released (e.g., mechanically, electrolytically, etc.)from a catheter. FIG. 7B illustrates the device 50 after it has beenfully constructed by positioning additional loops 52. Embolization coils62 may be inserted in the fundus 22 of the aneurysm 20 prior toconstruction of the device 50, for example as described above withrespect to FIG. 6A, or after construction of the device 50 (e.g., asillustrated in FIG. 7C).

Combinations of methods described herein are also possible. For example,a partially constructed device 50 may be positioned at the junction ofthe bifurcation 60, and then the device 50 may be fully constructed atthe junction of the bifurcation 60. In certain such embodiments, apartially constructed device 50 having some missing loops 52 may allowbetter access to the aneurysm 20 for easier placement of theembolization coils 62.

FIG. 8 illustrates another example embodiment of a generally sphericalvascular remodeling device 80. It will be appreciated that the device 80may be more compliant than the vasculature in which it is deployed suchthat it may be somewhat misshapen (e.g., non-spherical, for example asillustrated in FIG. 9B) after being deployed, and that the phrase“generally spherical” describes the shape of the device 80 when in anexpanded (e.g., fully expanded) state. Additionally, the phrase“generally spherical” distinguishes the device 80, which is generallyuniform in each dimension in an expanded state, from tubular stentshaving a small radial dimension and a large longitudinal dimension in anexpanded state. In some embodiments of a generally spherical device, anouter periphery of the device has a shape that deviates by between about10% and about 25% from an outer periphery of a mathematically perfectsphere. In some embodiments, the device 80 has a length and a width thatare within less than about 33% of each other (e.g., having a length of 6mm and a width of 8 mm, having a length of 6 mm and a width of 8 mm).Embodiments in which the width is greater than the length may beadvantageous due to a difference in porosity at a midpoint and an endproximate to an aneurysm. Embodiments in which the length is greaterthan the width may be advantageous for positioning a portion of thedevice 80 in a portion of the aneurysm 20 (e.g., to aid inembolization).

The device 80 comprises a first or distal end 81 and a second orproximal end 82 substantially opposite the first end 81. The device 80further comprises a plurality of filaments 84 extending between thefirst end 81 and the second end 82. The first end 81 extends outwardlyand the second end 82 extends outwardly to form a generally spherical(e.g., oval or oblong) shape similar to a football, a rugby ball, or awatermelon. In certain embodiments, the filaments 84 are coupled at thefirst end 81 and/or the second end 82 (e.g., by adhering, welding,soldering, combinations thereof, and the like). In the embodimentillustrated in FIG. 8, the device 80 comprises a lead or tail 83, whichmay be used for releasing and/or retracting the device 80 afterdeployment, as described herein. In certain embodiments, the device 80comprises a cut metallic sphere, a single filament, etc.

In certain embodiments, the device 80 is configured to be positioned ata junction of a bifurcation (e.g., a neurovascular bifurcation)comprising at least one afferent vessel, efferent vessels, and ananeurysm having a fundus and a neck. For example, in some embodiments,the device 80 is suitably dimensioned to fit in a junction of abifurcation (e.g., having a diameter between about 2 mm and about 12 mm,having a diameter between about 6 mm and about 8 mm, having a diameterless than about 12 mm, having a diameter greater than about 2 mm). Foranother example, in some embodiments, the device 80 is less rigid than ajunction of a bifurcation (e.g., due to the number of filaments 84, thematerial of the filaments 84, the thickness of the filaments 84, thespacing of the filaments 84, the shape of the filaments 84, combinationsthereof, and the like). In certain embodiments, the device 80 isconfigured to act as a scaffolding to inhibit or prevent herniation orprolapse of objects (e.g., embolization coils, thrombi, etc.) out of aneck of an aneurysm. For example, in some embodiments, the filaments 84are dense enough at the neck of the aneurysm that objects cannot pass.In certain embodiments, the device 80 is configured to permit perfusionof fluid (e.g., blood) to efferent vessels of a bifurcation. Forexample, in some embodiments, the device 80 is substantially devoid of acovering, mesh, or other material between the filaments 84, therebyallowing fluid to flow substantially unimpeded.

In some embodiments, at least one of the filaments 84 comprises aself-expanding and/or a shape-memory material (e.g., comprising Nitinol,CoCr alloy, etc.), thereby causing the device 80 to be self-expandingunder certain conditions (e.g., not restrained by a catheter). In someembodiments, at least one of the filaments 84 comprises a differentmaterial than others of the filaments 84 (e.g., some filaments 84comprising Nitinol and some filaments 84 comprising Nitinol andplatinum). In some embodiments, at least one of the filaments 84comprises a radiopaque material (e.g., platinum). In certain suchembodiments, an even number of filaments 84 (e.g., two, four, etc.)comprises a radiopaque material (e.g., platinum). In some embodiments,at least one of the filaments 84 comprises a radiopaque material (e.g.,platinum) at least partially wrapped (e.g., coiled) around aself-expanding material (e.g., Nitinol). In some embodiments, at leastone of the filaments 84 comprises a self-expanding material with aradiopaque core (e.g., Nitinol with a platinum core) or a radiopaquecoating (e.g., Nitinol coated with platinum, tantalum, etc. by physicalvapor deposition, chemical vapor deposition, plating, etc.). It will beappreciated that the amount and type of radiopaque material used maydepend, inter alia, on price, desired level of radiopacity, mechanicalproperties of the radiopaque material, and corrosion properties of theradiopaque material. In certain embodiments, the filaments 84 have asubstantially circular or ovoid cross section (e.g., embodiments, inwhich the filaments 84 comprise separate wires). In some embodiments,the filaments 84 have a substantially rectangular or flat cross section(e.g., embodiments, in which the filaments 84 comprise uncut portions ofa metallic tube, as described below). Other shapes of filaments 84 andcombinations of shapes of filaments 84 are also possible. In certainembodiments, the plurality of filaments 84 comprises between about sixand about twelve filaments 84. In certain embodiments, the plurality offilaments 84 comprises at least about six filaments 84, at least abouteight filaments 84, or at least about twelve filaments 84. Other numbersof filaments 84 are also possible.

In certain embodiments, at least some of the filaments 84 comprise apolymer. In some embodiments, at least some of the filaments 84 comprisea polymer that is bioabsorbable. In certain embodiments, at least someof the filaments 84 comprise polyglycolic acid (PGA), polylactic acid(PLA), poly(lactic-co-glycolic acid) (PLGA), poly-epsilon-caprolactone(PCL), naturally-derived bioabsorbable polymers (NDB), or combinationsthereof (e.g., a first group of the filaments 84 comprising PGA and asecond group of the filaments 84 comprising PLA, PLGA, PCL, and/or NDB,a first group of the filaments 84 comprising PLA and a second group ofthe filaments 84 comprising PGA, PLGA, PCL, and/or NDB, a first group ofthe filaments 84 comprising PLGA and a second group of the filaments 84comprising PLA, PGA, PCL, and/or NDB, a first group of the filaments 84comprising PCL and a second group of the filaments 84 comprising PGA,PLA, PLGA, and/or NDB, a first group of the filaments 84 comprising NDBand a second group of the filaments 84 comprising PGA, PLA, PLGA, and/orPCL, etc.). Other polymers are also possible. PGA, PLA, PLGA, PCL, andNDB are all bioabsorbable; however they have different rates ofbioabsorption. The bioabsorption rates of a single polymer can also varybased on, for example, blood characteristics, blood flow, filament 84dimensions, etc. PLA has the longest bioabsorption rate. In someembodiments, the bioabsorption rate of PLA is at least about ten months.In some embodiments, the bioabsorption rate of PLA is at least about oneyear. In some embodiments, the bioabsorption rate of PLA is at leastabout fourteen months. In some embodiments, the bioabsorption rate ofPLA is between about 10 months and about 14 months (e.g., about oneyear). In some embodiments, the bioabsorption rate of PGA is betweenabout 1 week and about 3 weeks. In some embodiments, the bioabsorptionrate of PGA is between about 2 weeks and about 4 weeks. Thebioabsorption rates of PLGA, PCL, and NDB are generally between thebioabsorption rates of PLA and PGA, and may depend on parameters suchas, for example, molecular weight (e.g., generally the higher themolecular weight, the longer the bioabsorption rate), structure (e.g.,depending on the arrangement of repeating units), etc. of the polymer.In some embodiments, PLGA, PCL, and NDB may have a bioabsorption ratebetween about 4 weeks and about 1 year. The bioabsorption rate generallyrefers to the time lose about 50% of strength. The polymer(s) used inthe device 80 may be selected based on the amount of time an aneurysmmay take to thrombose (e.g., based on fundus size, neck width, etc.).For example, if an aneurysm is expected to take one month to thromboseand the device 80 is expected to persist through thrombosis but not longthereafter, PGA may be selected. The polymer(s) used in the device 80may be selected based on the amount of time an aneurysm may take toobliterate (e.g., based on fundus size, neck width, etc.). For example,if an aneurysm is expected to take one year to obliterate and the device80 is expected to persist through obliteration, PLA may be selected.Other polymers or combinations of polymers can be selected based on theparticular aneurysm to be treated and the desired action and/orpersistence of the device 80 with respect to the aneurysm. Otherselection criteria are also possible. Different combinations of polymerswith different rates of bioabsorption can allow for selection of adesired rate of bioabsorption for the device 80. For example, a device80 with a combination of PGA and PLA filaments 84 may have a rate ofbioabsorption in between the rate of bioabsorption of a device 80comprising only filaments 84 comprising PGA and the rate ofbioabsorption of a device 80 comprising only filaments 84 comprisingPLA. In some embodiments, the coupling of the filaments 84 may alsocomprise a bioabsorbable polymer. For example, the filaments 84 may becoupled at the proximal end 82 of the device 80 by intertwining thebioabsorbable filaments 84 or the filaments 84 may be coupled at theproximal end 82 of the device 80 using a separate bioabsorbablecomponent.

The device 80 comprises a plurality of perforations or cells 86 betweenthe filaments 84. In certain embodiments, a percentage of the outersurface of the device 80 covered by the filaments 84 is between about25% and about 40%. In certain embodiments, a percentage of the outersurface of the device 80 covered by the cells 86 is between about 60%and about 75%. Other porosities are also possible. In some embodiments,porosity distally increases between the second end 82 and an approximatemidpoint (e.g., approximately at the line A-A in FIG. 8) and distallydecreases between the approximate midpoint and the first end 81. Forexample, cross-sections taken along the lines A-A and B-B in FIG. 8 eachhave the same number of filaments 84, but at the cross-section A-A thefilaments 84 are spaced further apart from each other than at thecross-section B-B. As an example, if the device comprises ten filaments84 each having a thickness of 0.5 mm, the porosity at the cross-sectionA-A would be about 80% with an example circumference of about 25 mm:

100%×[1−(≈0.5 mm/filament×10 filaments/≈25 mm)]80%

and the porosity at the cross-section B-B would be about 33% with anexample circumference of about 7.5 mm:

100%×[1−(4.5 mm/filament×10 filaments/≈7.5 mm)]33%.

High porosity proximate to a midpoint of the device 80 may provide goodfluid flow to efferent vessels. Low porosity proximate to the first end81 of the device 80 may provide good scaffolding properties.

In some embodiments, the device 80 further comprises a radiopaque marker88 proximate to the first end 81 and/or a radiopaque marker 89 proximateto the second end 82. In certain embodiments, the radiopaque marker 88may extend at least partially into the aneurysm 20 when the device 80 ispositioned at the junction of a bifurcation. In some embodiments, theradiopaque markers 88, 89 may comprise a sleeve positioned or wrappedaround the filaments 84, thereby coupling the filaments 84. Theradiopaque markers 88, 89 may aid in positioning the device 80 at thejunction of a bifurcation.

In some embodiments, the device 80 further comprises a covering (e.g.,comprising a porous or non-porous polymer) proximate to the first end81. In some embodiments, the covering improves the scaffoldingproperties of the device 80 by reducing the porosity at the first end81, thereby further inhibiting the herniation or prolapse of embolicmaterial from the aneurysm 20. In certain embodiments, the covering maybe attached to the device 80 by sewing the covering from a pre-formedthin film. In certain embodiments, the covering may be mechanicallyattached (e.g., wrapped around, looped through, etc.) the filaments 84.In certain embodiments, the covering may be deposited (e.g., viaphysical vapor deposition, chemical vapor deposition, etc.) on thefilaments 84. Other portions of the device 80 may also comprise acovering.

FIGS. 9A-9C illustrate an example embodiment of a method for treating ananeurysm 20 using the device 80. FIG. 9A illustrates a confluence ofafferent and efferent vessels or “junction” at a bifurcation 60 havingan aneurysm 20. In some embodiments, the vessels are neurovascular orcranial. The aneurysm 20 is illustrated with a plurality of embolizationcoils 62 having been inserted in the fundus 22 of the aneurysm 20. Itwill be appreciated that the embolization coils 62 may be a singleembolization coil or other embolic material. A catheter 92 (e.g., amicrocatheter), at least partially containing a constricted orcompressed device 80, is also shown in the afferent vessel. The catheter92 is small enough and flexible enough to be routed through thevasculature and situated proximate to the aneurysm 20. In someembodiments, the embolization coils 62 are inserted in the fundus 22 ofthe aneurysm 20 using the catheter 92. In some embodiments, theembolization coils 62 are inserted in the fundus 22 of the aneurysm 20using a different catheter. In certain such embodiments, a guidewire maybe used to guide both catheters.

FIG. 9B illustrates the bifurcation 60 after the device 80 has beendeployed from the catheter 92 (e.g., by being pushed out with a plunger,by retracting the catheter 92 while the device 80 remains stationary,etc.). After being deployed from the catheter 92, the device 80 mayexpand. In some embodiments, the device 80 comprises a self-expandingand/or a shape-memory material that automatically expands towards anuncompressed state or expands towards an uncompressed state upon theapplication of warm fluid (e.g., saline). The device 80 maysubstantially conform to the shape of the junction of the bifurcation 60(e.g., not substantially including portions extending into the afferentand efferent vessels) and locks into place across the ostia of theafferent and efferent vessels and the neck 24 of the aneurysm 20. Thedevice 80 at least partially covers the neck 24 of the aneurysm 20 aswell as the afferent and efferent vessels, but does not need to divertflow. The device 80 acts as a scaffolding to inhibit or preventherniation or prolapse of objects such as the embolization coils 62and/or thrombi out of the aneurysm 24. The device 80 also allowsperfusion of fluid (e.g., blood) from the afferent vessel(s) to theefferent vessel(s).

FIG. 9C illustrates the bifurcation 60 after the device 80 has beenreleased from the catheter 92. In some embodiments, the device 80 isreleased mechanically (e.g., by a release mechanism). In someembodiments, the device 80 is released electrolytically (e.g., byapplying a small current until a portion of the tail 83 proximal to thedevice 80 corrodes away, as illustrated by the gap 95). The catheter 92is then withdrawn from the bifurcation 60, thereby leaving orpermanently positioning the device 80 at the junction of the bifurcation60.

It will be appreciated that the term “permanently” does not mean thatthe device 80 is impossible to remove at a later time. In someembodiments, the device 80 may be retracted into the catheter 92 afterbeing deployed from the catheter 92 (e.g., by pulling on the tail 83).The device 80 may then be deployed, for example at a new angle, at a newrotational position, more proximal or distal to an afferent vesseland/or an efferent vessel, etc. For example, although the device 80expands towards an uncompressed state after deployment, the resultingshape of the device 80 at the junction of the bifurcation 60 may varydepending on the details of the deployment from the catheter 92 becausethe device 80 adapts to the shape of the anatomy (e.g., due to the size,shape, number, etc. of the loops 82). Once the user is satisfied withproperties of the device 80 (e.g., position, tilt, rotation, shape,interaction with the vessels, etc.), the device 80 may be released asdescribed herein.

In the embodiment illustrated in FIGS. 9A-9C, the embolization coils 62are inserted in the fundus 22 of the aneurysm 20 before the device 80has been deployed from the catheter 92 (e.g., using the catheter 92 toinsert the embolization coils 62). In the embodiments illustrated inFIGS. 10A-10C, the embolization coils 62 are inserted in the fundus 22of the aneurysm 20 after the device 80 has been released from thecatheter 92 (e.g., using the catheter 92 to insert the embolizationcoils 62). Combinations are also possible. For example, the embolizationcoils 62 may be inserted in the fundus 22 of the aneurysm 20 after thedevice 80 has been deployed from the catheter 92, but prior to thedevice 80 being released from the catheter 92. For another example, theembolization coils 62 may be inserted into the fundus 22 of the aneurysm20 after the device 80 has been deployed from the catheter 92 (e.g., ina coil state), and the device 80 may be retracted and redeployed fromthe catheter 92 (e.g., in a final state).

In certain embodiments, the filaments 84 comprise a bioabsorbablepolymer. This bioabsorbability can be advantageous in conjunction withpermanent placement of the device 80. For example, after thrombosis ofthe aneurysm following treatment, the device 80 may no longer be neededto inhibit herniation of material. Certain bioabsorbable embodiments ofthe device 80 may advantageously inhibit herniation during thrombosis ofthe aneurysm, but bioabsorb when they may no longer be needed to inhibitherniation. In certain embodiments in which the coupling of the proximalend 82 of the device 80 comprises a bioabsorbable polymer, the couplingmay absorb over time, releasing the filaments 84. Once released, thefilaments 84 may extend towards and may flatten against the wall of theafferent vessel. This capability may advantageously clear the interiorsection of the afferent vessel, restoring normal blood flow therein(e.g., in embodiments in which the coupled proximal end may have alteredblood flow). In some embodiments, this capability may clear the interiorsection of the afferent vessel before bioabsorption of the filament 84is complete. In certain such embodiments, the coupling may comprise amaterial that bioabsorbs faster than the filaments (e.g., the couplingcomprising PGA and the filaments comprising PLA). This can makepermanent placement, or release of the device 80, a less consequentialprocedure as a device 80 comprising bioabsorbable filaments 84 will notremain in the vasculature permanently.

FIG. 11 illustrates yet another example embodiment of a generallyspherical vascular remodeling device 110. It will be appreciated thatthe device 110 may be more compliant than the vasculature in which it isdeployed such that it may be somewhat misshapen (e.g., non-spherical,for example as illustrated in FIG. 12) after being deployed, and thatthe phrase “generally spherical” describes the shape of the device 110when in an expanded (e.g., fully expanded) state. Additionally, thephrase “generally spherical” distinguishes the device 110, which isgenerally uniform in each dimension in an expanded state, from tubularstents having a small radial dimension and a large longitudinaldimension in an expanded state. In some embodiments of a generallyspherical device, an outer periphery of the device has a shape thatdeviates by between about 10% and about 25% from an outer periphery of amathematically perfect sphere. In some embodiments, the device 110 has alength and a width that are within less than about 33% of each other(e.g., having a length of 6 mm and a width of 8 mm, having a length of 6mm and a width of 8 mm). Embodiments in which the width is greater thanthe length may be advantageous due to a difference in porosity at amidpoint and an end proximate to an aneurysm. Embodiments in which thelength is greater than the width may be advantageous for positioning aportion of the device 110 in a portion of the aneurysm 20 (e.g., to aidin embolization).

The device 110 comprises a first or distal end 111 and a second orproximal end 112 substantially opposite the first end 111. The device110 further comprises a plurality of filaments 114 extending between thefirst end 111 and the second end 112. In the device 110 illustrated inFIG. 11, the first end 111 extends inwardly and the second end 112extends outwardly to form a generally spherical shape similar to apumpkin, a garlic bulb, or a rutabaga. In some embodiments, thefilaments 114 are coupled at a position proximal to a bend at a distalend of the device 110 (e.g., as illustrated by the dimension d in FIG.11). In certain embodiments, the filaments 114 are coupled at the firstend 111 and/or the second end 112 (e.g., by adhering, welding,soldering, combinations thereof, and the like). In the embodimentillustrated in FIG. 11, the device 110 comprises a lead or tail 113,which may be used for releasing and/or retracting the device 110 afterdeployment, as described herein. In certain embodiments, the device 110comprises a cut metallic sphere, a single filament, etc. It will beappreciated that a device in which the first end extends outwardly andthe second end extends inwardly and a device in which the first endextends inwardly and the second end extends inwardly are also possible.

In certain embodiments, the device 110 is configured to be positioned ata junction of a bifurcation (e.g., a neurovascular bifurcation)comprising at least one afferent vessel, efferent vessels, and ananeurysm having a fundus and a neck. For example, in some embodiments,the device 110 is suitably dimensioned to fit in a junction of abifurcation (e.g., having a diameter between about 2 mm and about 12 mm,having a diameter between about 6 mm and about 8 mm, having a diameterless than about 12 mm, having a diameter greater than about 2 mm). Foranother example, in some embodiments, the device 110 is less rigid thana junction of a bifurcation (e.g., due to the number of filaments 114,the material of the filaments 114, the thickness of the filaments 114,the spacing of the filaments 114, the shape of the filaments 114,combinations thereof, and the like). In certain embodiments, the device110 is configured to act as a scaffolding to inhibit or preventherniation or prolapse of objects (e.g., embolization coils, thrombi,etc.) out of a neck of an aneurysm. For example, in some embodiments,the filaments 114 are dense enough at the neck of the aneurysm thatobjects cannot pass. In certain embodiments, the device 110 isconfigured to permit perfusion of fluid (e.g., blood) to efferentvessels of a bifurcation. For example, in some embodiments, the device110 is substantially devoid of a covering, mesh, or other materialbetween the filaments 114, thereby allowing fluid to flow substantiallyunimpeded.

In some embodiments, at least one of the filaments 114 comprises aself-expanding and/or a shape-memory material (e.g., comprising Nitinol,CoCr alloy, etc.), thereby causing the device 110 to be self-expandingunder certain conditions (e.g., not restrained by a catheter). In someembodiments, at least one of the filaments 114 comprises a differentmaterial than others of the filaments 114 (e.g., some filaments 114comprising Nitinol and some filaments 114 comprising Nitinol andplatinum). In some embodiments, at least one of the filaments 114comprises a radiopaque material (e.g., platinum). In certain suchembodiments, an even number of filaments 84 (e.g., two, four, etc.)comprises a radiopaque material (e.g., platinum). In some embodiments,at least one of the filaments 84 comprises a radiopaque material (e.g.,platinum) at least partially wrapped (e.g., coiled) around aself-expanding material (e.g., Nitinol). In some embodiments, at leastone of the filaments 84 comprises a self-expanding material with aradiopaque core (e.g., Nitinol with a platinum core) or a radiopaquecoating (e.g., Nitinol coated with platinum, tantalum, etc. by physicalvapor deposition, chemical vapor deposition, plating, etc.). It will beappreciated that the amount and type of radiopaque material used maydepend, inter alia, on price, desired level of radiopacity, mechanicalproperties of the radiopaque material, and corrosion properties of theradiopaque material. In certain embodiments, the filaments 114 have asubstantially circular or ovoid cross section (e.g., embodiments, inwhich the filaments 84 comprise separate wires). In some embodiments,the filaments 114 have a substantially rectangular or flat cross section(e.g., embodiments, in which the filaments 84 comprise uncut portions ofa metallic tube). Other shapes of filaments 114 and combinations ofshapes of filaments 114 are also possible. In certain embodiments, theplurality of filaments 84 comprises between about six and about twelvefilaments 114. In certain embodiments, the plurality of filaments 114comprises at least about six filaments 114, at least about eightfilaments 114, or at least about twelve filaments 114. Other numbers offilaments 114 are also possible.

In certain embodiments, at least some of the filaments 114 comprise apolymer. In some embodiments, at least some of the filaments 114comprise a polymer that is bioabsorbable. In certain embodiments, atleast some of the filaments 114 comprise polyglycolic acid (PGA),polylactic acid (PLA), poly(lactic-co-glycolic acid) (PLGA),poly-epsilon-caprolactone (PCL), naturally-derived bioabsorbablepolymers (NDB), or combinations thereof (e.g., a first group of thefilaments 114 comprising PGA and a second group of the filaments 114comprising PLA, PLGA, PCL, and/or NDB, a first group of the filaments114 comprising PLA and a second group of the filaments 114 comprisingPGA, PLGA, PCL, and/or NDB, a first group of the filaments 114comprising PLGA and a second group of the filaments 114 comprising PLA,PGA, PCL, and/or NDB, a first group of the filaments 114 comprising PCLand a second group of the filaments 114 comprising PGA, PLA, PLGA,and/or NDB, a first group of the filaments 114 comprising NDB and asecond group of the filaments 114 comprising PGA, PLA, PLGA, and/or PCL,etc.). Other polymers are also possible. PGA, PLA, PLGA, PCL, and NDBare all bioabsorbable; however they have different rates ofbioabsorption. The bioabsorption rates of a single polymer can also varybased on, for example, blood characteristics, blood flow, filament 114dimensions, etc. PLA has the longest bioabsorption rate. In someembodiments, the bioabsorption rate of PLA is at least about ten months.In some embodiments, the bioabsorption rate of PLA is at least about oneyear. In some embodiments, the bioabsorption rate of PLA is at leastabout fourteen months. In some embodiments, the bioabsorption rate ofPLA is between about 10 months and about 14 months (e.g., about oneyear). In some embodiments, the bioabsorption rate of PGA is betweenabout 1 week and about 3 weeks. In some embodiments, the bioabsorptionrate of PGA is between about 2 weeks and about 4 weeks. Thebioabsorption rates of PLGA, PCL, and NDB are generally between thebioabsorption rates of PLA and PGA, and may depend on parameters suchas, for example, molecular weight (e.g., generally the higher themolecular weight, the longer the bioabsorption rate), structure (e.g.,depending on the arrangement of repeating units), etc. of the polymer.In some embodiments, PLGA, PCL, and NDB may have a bioabsorption ratebetween about 4 weeks and about 1 year. The bioabsorption rate generallyrefers to the time lose about 50% of strength. The polymer(s) used inthe device 110 may be selected based on the amount of time an aneurysmmay take to thrombose (e.g., based on fundus size, neck width, etc.).For example, if an aneurysm is expected to take one month to thromboseand the device 110 is expected to persist through thrombosis but notlong thereafter, PGA may be selected. The polymer(s) used in the device110 may be selected based on the amount of time an aneurysm may take toobliterate (e.g., based on fundus size, neck width, etc.). For example,if an aneurysm is expected to take one year to obliterate and the device110 is expected to persist through obliteration, PLA may be selected.Other polymers or combinations of polymers can be selected based on theparticular aneurysm to be treated and the desired action and/orpersistence of the device 110 with respect to the aneurysm. Otherselection criteria are also possible. Different combinations of polymerswith different rates of bioabsorption can allow for selection of adesired rate of bioabsorption for the device 110. For example, a device110 with a combination of PGA and PLA filaments 114 may have a rate ofbioabsorption in between the rate of bioabsorption of a device 110comprising only filaments 114 comprising PGA and the rate ofbioabsorption of a device 110 comprising only filaments 114 comprisingPLA. In some embodiments, the coupling of the filaments 114 may alsocomprise a bioabsorbable polymer. For example, the filaments 114 may becoupled at the proximal end 112 of the device 110 by intertwining thebioabsorbable filaments 114 or the filaments 114 may be coupled at theproximal end 112 of the device 110 using a separate bioabsorbablecomponent.

As described herein, certain embodiments comprising bioabsorbablefilaments (e.g., the filaments 114) can be advantageous in conjunctionwith permanent placement of the device (e.g., the device 110). Incertain embodiments in which the coupling of the proximal end 112 of thedevice 110 comprises a bioabsorbable polymer, the coupling may absorbover time, releasing the filaments 114. Once released, the filaments 114may extend towards and may flatten against the wall of the afferentvessel. This capability may advantageously clear the interior section ofthe afferent vessel, restoring normal blood flow therein (e.g., inembodiments in which the coupled proximal end may have altered bloodflow). In some embodiments, this capability may clear the interiorsection of the afferent vessel before bioabsorption of the filament 114is complete. In certain such embodiments, the coupling may comprise amaterial that bioabsorbs faster than the filaments (e.g., the couplingcomprising PGA and the filaments comprising PLA).

The device 110 comprises a plurality of perforations or cells 116between the filaments 114. In certain embodiments, a percentage of theouter surface of the device 110 covered by the filaments 114 is betweenabout 25% and about 40%. In certain embodiments, a percentage of theouter surface of the device 110 covered by the cells 116 is betweenabout 60% and about 75%. Other porosities are also possible. In someembodiments, porosity distally increases between the second end 112 andan approximate midpoint and distally decreases between the approximatemidpoint and the first end 111.

In some embodiments, the device 110 further comprises a radiopaquemarker 118 proximate to the first end 111 and/or a radiopaque marker 119proximate to the second end 112. In certain embodiments, the radiopaquemarker 118 may extend at least partially into the aneurysm 20 when thedevice 110 is positioned at the junction of a bifurcation. In someembodiments, the radiopaque markers 118, 119 may comprise a sleevesituated or wrapped around the filaments 114, thereby coupling thefilaments 114. The radiopaque markers 118, 119 may aid in positioningthe device 110 at the junction of a bifurcation.

In some embodiments, the device 110 further comprises a covering (e.g.,comprising a porous or non-porous polymer) proximate to the first end111. In some embodiments, the covering improves the scaffoldingproperties of the device 110 by reducing the porosity at the first end111, thereby further inhibiting the herniation or prolapse of embolicmaterial from the aneurysm 20. In certain embodiments, the covering maybe attached to the device 110 by sewing the covering from a pre-formedthin film. In certain embodiments, the covering may be mechanicallyattached (e.g., wrapped around, looped through, etc.) the filaments 114.In certain embodiments, the covering may be deposited (e.g., viaphysical vapor deposition, chemical vapor deposition, etc.) on thefilaments 114. Other portions of the device 110 may also comprise acovering.

FIG. 12 illustrates an example embodiment of treating an aneurysm 20using the device 110. The junction at the bifurcation 60, including thetreated aneurysm 20, illustrated in FIG. 12 may be the result ofperforming a method similar to the method described with respect toFIGS. 9A-9C, the result of performing a method similar to the methoddescribed with respect to FIGS. 10A-10C, combinations thereof, and thelike.

As described above, the term “bifurcation” described herein is notlimited to the particular vasculature illustrated in FIGS. 6A-7C,9A-10C, and 12, for example having efferent vessels at substantiallydifferent angles, having efferent vessels that are substantiallydifferent sizes, and/or having a different quantity of efferent vesselsand/or the aneurysm of the bifurcation may be offset with respect to thejunction (e.g., having a neck substantially open to one efferentvessel), tilted with respect to a plane created by the vessels (e.g.,into or out of the page), etc.

FIG. 13 illustrates still another example embodiment of a generallyspherical vascular remodeling device 130. It will be appreciated thatthe device 130 may be more compliant than the vasculature in which it isdeployed such that it may be somewhat misshapen (e.g., non-spherical)after being deployed, and that the phrase “generally spherical”describes the shape of the device 130 when in an expanded (e.g., fullyexpanded) state. Additionally, the phrase “generally spherical”distinguishes the device 130, which is generally uniform in eachdimension in an expanded state, from tubular stents having a smallradial dimension and a large longitudinal dimension in an expandedstate. In some embodiments of a generally spherical device, an outerperiphery of the device has a shape that deviates by between about 10%and about 25% from an outer periphery of a mathematically perfectsphere. In some embodiments, the device 130 has a length and a widththat are within less than about 33% of each other (e.g., having a lengthof 6 mm and a width of 8 mm, having a length of 6 mm and a width of 8mm). Embodiments in which the width is greater than the length may beadvantageous due to a difference in porosity at a midpoint and an endproximate to an aneurysm. Embodiments in which the length is greaterthan the width may be advantageous for positioning a portion of thedevice 130 in a portion of the aneurysm 20 (e.g., to aid inembolization).

The device 130 comprises a first or distal end 131 and a second orproximal end 132 substantially opposite the first end 131. The device130 further comprises a plurality of filaments 134 extending between thefirst end 131 and the second end 132. In the device 130 illustrated inFIG. 13, the first end 131 extends outwardly and the second end 132extends outwardly to form a generally spherical shape similar to atwisted sphere (e.g., after rotating one or both ends 81, 82 of thedevice 80 illustrated in FIG. 8 with respect to each other). In certainembodiments, the filaments 134 are coupled at the first end 131 and/orthe second end 132 (e.g., by adhering, welding, soldering, combinationsthereof, and the like). In contrast to the filaments 84 of the device 80illustrated in FIG. 8, which in some embodiments are straight enough toform a plane, the filaments 134 of the device 130 are longitudinallyangled at or adjacent to at least the second end 132. In the embodimentillustrated in FIG. 13, the device 130 comprises a lead or tail 133,which may be used for releasing and/or retracting the device 130 afterdeployment, as described herein. In some embodiments, deployment and/orretraction of the device 130 uses less force than retraction of, forexample, the devices 50, 80, 110. In certain embodiments, the device 130comprises a cut metallic sphere, a single filament, etc.

In certain embodiments, the device 130 is configured to be positioned ata junction of a bifurcation (e.g., a neurovascular bifurcation)comprising at least one afferent vessel, efferent vessels, and ananeurysm having a fundus and a neck. For example, in some embodiments,the device 130 is suitably dimensioned to fit in a junction of abifurcation (e.g., having a diameter between about 2 mm and about 12 mm,having a diameter between about 6 mm and about 8 mm, having a diameterless than about 12 mm, having a diameter greater than about 2 mm). Foranother example, in some embodiments, the device 130 is less rigid thana junction of a bifurcation (e.g., due to the number of filaments 134,the material of the filaments 134, the thickness of the filaments 134,the spacing of the filaments 134, the shape of the filaments 134,combinations thereof, and the like). In certain embodiments, the device130 is configured to act as a scaffolding to inhibit or preventherniation or prolapse of objects (e.g., embolization coils, thrombi,etc.) out of a neck of an aneurysm. For example, in some embodiments,the filaments 134 are dense enough at the neck of the aneurysm thatobjects cannot pass. In certain embodiments, the device 130 isconfigured to permit perfusion of fluid (e.g., blood) to efferentvessels of a bifurcation. For example, in some embodiments, the device130 is substantially devoid of a covering, mesh, or other materialbetween the filaments 134, thereby allowing fluid to flow substantiallyunimpeded.

In some embodiments, at least one of the filaments 134 comprises aself-expanding and/or a shape-memory material (e.g., comprising Nitinol,CoCr alloy, etc.), thereby causing the device 130 to be self-expandingunder certain conditions (e.g., not restrained by a catheter). In someembodiments, at least one of the filaments 134 comprises a differentmaterial than others of the filaments 134 (e.g., some filaments 134comprising Nitinol and some filaments 134 comprising Nitinol andplatinum). In some embodiments, at least one of the filaments 134comprises a radiopaque material (e.g., platinum). In certain suchembodiments, an even number of filaments 84 (e.g., two, four, etc.)comprises a radiopaque material (e.g., platinum). In some embodiments,at least one of the filaments 84 comprises a radiopaque material (e.g.,platinum) at least partially wrapped (e.g., coiled) around aself-expanding material (e.g., Nitinol). In some embodiments, at leastone of the filaments 84 comprises a self-expanding material with aradiopaque core (e.g., Nitinol with a platinum core) or a radiopaquecoating (e.g., Nitinol coated with platinum, tantalum, etc. by physicalvapor deposition, chemical vapor deposition, plating, etc.). It will beappreciated that the amount and type of radiopaque material used maydepend, inter alia, on price, desired level of radiopacity, mechanicalproperties of the radiopaque material, and corrosion properties of theradiopaque material. In certain embodiments, the filaments 134 have asubstantially circular or ovoid cross section (e.g., embodiments, inwhich the filaments 84 comprise separate wires). In some embodiments,the filaments 134 have a substantially rectangular or flat cross section(e.g., embodiments, in which the filaments 84 comprise uncut portions ofa metallic tube). Other shapes of filaments 134 and combinations ofshapes of filaments 134 are also possible. In certain embodiments, theplurality of filaments 84 comprises between about six and about twelvefilaments 134. In certain embodiments, the plurality of filaments 134comprises at least about six filaments 134, at least about eightfilaments 134, or at least about twelve filaments 134. Other numbers offilaments 134 are also possible.

In certain embodiments, at least some of the filaments 134 comprise apolymer. In some embodiments, at least some of the filaments 134comprise a polymer that is bioabsorbable. In certain embodiments, atleast some of the filaments 134 comprise polyglycolic acid (PGA),polylactic acid (PLA), poly(lactic-co-glycolic acid) (PLGA),poly-epsilon-caprolactone (PCL), naturally-derived bioabsorbablepolymers (NDB), or combinations thereof (e.g., a first group of thefilaments 134 comprising PGA and a second group of the filaments 134comprising PLA, PLGA, PCL, and/or NDB, a first group of the filaments134 comprising PLA and a second group of the filaments 134 comprisingPGA, PLGA, PCL, and/or NDB, a first group of the filaments 134comprising PLGA and a second group of the filaments 134 comprising PLA,PGA, PCL, and/or NDB, a first group of the filaments 134 comprising PCLand a second group of the filaments 134 comprising PGA, PLA, PLGA,and/or NDB, a first group of the filaments 134 comprising NDB and asecond group of the filaments 134 comprising PGA, PLA, PLGA, and/or PCL,etc.). Other polymers are also possible. PGA, PLA, PLGA, PCL, and NDBare all bioabsorbable; however they have different rates ofbioabsorption. The bioabsorption rates of a single polymer can also varybased on, for example, blood characteristics, blood flow, filament 134dimensions, etc. PLA has the longest bioabsorption rate. In someembodiments, the bioabsorption rate of PLA is at least about ten months.In some embodiments, the bioabsorption rate of PLA is at least about oneyear. In some embodiments, the bioabsorption rate of PLA is at leastabout fourteen months. In some embodiments, the bioabsorption rate ofPLA is between about 10 months and about 14 months (e.g., about oneyear). In some embodiments, the bioabsorption rate of PGA is betweenabout 1 week and about 3 weeks. In some embodiments, the bioabsorptionrate of PGA is between about 2 weeks and about 4 weeks. Thebioabsorption rates of PLGA, PCL, and NDB are generally between thebioabsorption rates of PLA and PGA, and may depend on parameters suchas, for example, molecular weight (e.g., generally the higher themolecular weight, the longer the bioabsorption rate), structure (e.g.,depending on the arrangement of repeating units), etc. of the polymer.In some embodiments, PLGA, PCL, and NDB may have a bioabsorption ratebetween about 4 weeks and about 1 year. The bioabsorption rate generallyrefers to the time lose about 50% of strength. The polymer(s) used inthe device 130 may be selected based on the amount of time an aneurysmmay take to thrombose (e.g., based on fundus size, neck width, etc.).For example, if an aneurysm is expected to take one month to thromboseand the device 130 is expected to persist through thrombosis but notlong thereafter, PGA may be selected. The polymer(s) used in the device130 may be selected based on the amount of time an aneurysm may take toobliterate (e.g., based on fundus size, neck width, etc.). For example,if an aneurysm is expected to take one year to obliterate and the device130 is expected to persist through obliteration, PLA may be selected.Other polymers or combinations of polymers can be selected based on theparticular aneurysm to be treated and the desired action and/orpersistence of the device 130 with respect to the aneurysm. Otherselection criteria are also possible. Different combinations of polymerswith different rates of bioabsorption can allow for selection of adesired rate of bioabsorption for the device 130. For example, a device130 with a combination of PGA and PLA filaments 134 may have a rate ofbioabsorption in between the rate of bioabsorption of a device 130comprising only filaments 134 comprising PGA and the rate ofbioabsorption of a device 130 comprising only filaments 134 comprisingPLA. In some embodiments, the coupling of the filaments 134 may alsocomprise a bioabsorbable polymer. For example, the filaments 134 may becoupled at the proximal end 132 of the device 130 by intertwining thebioabsorbable filaments 134 or the filaments 134 may be coupled at theproximal end 132 of the device 130 using a separate bioabsorbablecomponent.

As described herein, certain embodiments comprising bioabsorbablefilaments (e.g., the filaments 134) can be advantageous in conjunctionwith permanent placement of the device (e.g., the device 130). Incertain embodiments in which the coupling of the proximal end 132 of thedevice 130 comprises a bioabsorbable polymer, the coupling may absorbover time, releasing the filaments 134. Once released, the filaments 134may extend towards and may flatten against the wall of the afferentvessel. This capability may advantageously clear the interior section ofthe afferent vessel, restoring normal blood flow therein (e.g., inembodiments in which the coupled proximal end may have altered bloodflow). In some embodiments, this capability may clear the interiorsection of the afferent vessel before bioabsorption of the filament 134is complete. In certain such embodiments, the coupling may comprise amaterial that bioabsorbs faster than the filaments (e.g., the couplingcomprising PGA and the filaments comprising PLA).

The device 130 comprises a plurality of perforations or cells 136between the filaments 134. In certain embodiments, a percentage of theouter surface of the device 130 covered by the filaments 134 is betweenabout 25% and about 40%. In certain embodiments, a percentage of theouter surface of the device 130 covered by the cells 136 is betweenabout 60% and about 75%. Other porosities are also possible. In someembodiments, porosity distally increases between the second end 132 andan approximate midpoint and distally decreases between the approximatemidpoint and the first end 131.

In some embodiments, the device 130 further comprises a radiopaquemarker 138 proximate to the first end 131 and/or a radiopaque marker 139proximate to the second end 132. In certain embodiments, the radiopaquemarker 138 may extend at least partially into the aneurysm 20 when thedevice 130 is positioned at the junction of a bifurcation. In someembodiments, the radiopaque markers 138, 139 may comprise a sleevesituated or wrapped around the filaments 134, thereby coupling thefilaments 134. The radiopaque markers 138, 139 may aid in positioningthe device 130 at the junction of a bifurcation.

In some embodiments, the device 130 further comprises a covering (e.g.,comprising a porous or non-porous polymer) proximate to the first end131. In some embodiments, the covering improves the scaffoldingproperties of the device 130 by reducing the porosity at the first end131, thereby further inhibiting the herniation or prolapse of embolicmaterial from the aneurysm 20. In certain embodiments, the covering maybe attached to the device 130 by sewing the covering from a pre-formedthin film. In certain embodiments, the covering may be mechanicallyattached (e.g., wrapped around, looped through, etc.) the filaments 134.In certain embodiments, the covering may be deposited (e.g., viaphysical vapor deposition, chemical vapor deposition, etc.) on thefilaments 134. Other portions of the device 130 may also comprise acovering.

The device 130 may be positioned and retracted as described, forexample, by performing a method similar to the method described withrespect to FIGS. 9A-9C, by performing a method similar to the methoddescribed with respect to FIGS. 10A-10C, combinations thereof, and thelike. As described above, the device 130 may be particularlyadvantageous for embodiments in which retraction and redeployment of thedevice 130 is likely.

FIG. 14 illustrates an example embodiment of a generally sphericalvascular remodeling device 140 (e.g., having a football shape similar tothe device 80) at a stage of an example manufacturing process comprisingcutting and shaping a metallic tube (e.g., a laser cut hypotube). Insome embodiments, the starting tube has a diameter between about 0.5 mmand about 3 mm or between about 1 mm and about 2 mm (e.g., about 1 mm,about 1.5 mm, about 2 mm, etc.). Other diameters are also possible. Thedevice has a first or distal end 141 and a second or proximal end 142substantially opposite the first end 141. A laser may cut out portions146 of the tube, leaving a plurality of filaments 144 extending betweenthe first end 141 and the second end 142. In the embodiment illustratedin FIG. 14, the filaments 144 are coupled at the first end 141 and thesecond end 142 (e.g., due to being integrally formed with the metallictube and not cut away from each other). In some embodiments, a lead ortail, which may be used for releasing and/or retracting the device 140after deployment, as described herein, may be attached to the device 140(e.g., by adhering, soldering, welding, etc.). In certain embodiments, atail 143 may be integral with the device 140 by being defined by the cuttube.

In some embodiments, the device 140 further comprises a radiopaquemarker 148 proximate to the first end 141 and/or a radiopaque marker 149proximate to the second end 142. In certain embodiments, the radiopaquemarker 148 may extend at least partially into the aneurysm 20 when thedevice 140 is positioned at the junction of a bifurcation. In someembodiments, the radiopaque markers 148, 149 may be integral with thedevice by being defined by the cut tube. The radiopaque markers 148, 149may aid in positioning the device 140 at the junction of a bifurcation.

The cut tube can then be expanded into a generally spherical shapethrough shape setting using a heat treatment process. The shape settingprocess may include several steps comprising of successively increasingdiameters of generally spherical shapes using appropriate tooling tostretch and confine the cut tube into a new shape while heat treatingit. At the end of the each heat treatment step, the cut tube assumes theshape in which it was confined during the heat treatment process. Thisprocess is then repeated to form a slightly larger size and a shapecloser to the end product. The final shape (e.g., a football shapesimilar to the device 80) and size may obtained by several such steps.Other devices described herein (e.g., the devices 50, 110, 130) may alsobe formed using cut a metallic tube that is reshaped after being cut,although it will be appreciated that the pattern of the initial cut maybe different, such that details about possible materials, dimensions,porosities, deployment methods, possibly coverings, etc. are notprovided.

The disclosures of U.S. Provisional Patent App. No. 61/082,579, filedJul. 22, 2008, and U.S. patent application Ser. No. 12/506,945, filedJul. 21, 2009, may be relevant to certain of the generally sphericalvascular remodeling devices described herein, and the disclosure each ofthose applications is incorporated herein by reference in its entirety.

Certain devices described herein may be advantageously used to treataneurysms having a neck ratio (a ratio of fundus width to neck width)greater than about 2 to 1 and/or a neck width greater than about 4 mm.In treatment of such aneurysms, embolization coils may be prone toherniating into parent vessels because the size and/or shape of theaneurysm is not conducive to maintaining the coils in their insertedlocus. In certain such embodiments, embolization coils are inserted inthe fundus of the aneurysm after positioning a generally sphericaldevice so that the embolization coils do not have an opportunity toherniate. It will be appreciated that certain devices described hereinmay also be used to treat aneurysms having a neck ratio less than about2 to 1 and/or a neck width less than about 4 mm. In certain suchembodiments, embolization coils are inserted in the fundus of theaneurysm before positioning a generally spherical device.

Certain devices described herein may advantageously be a singlegenerally spherical device placed at a junction of a bifurcation ratherthan a plurality of tubular bifurcations. Certain such devices can spana neck of an aneurysm as well as arterial ostia. Positioning suchdevices may be less complicated, thereby reducing risks associated with,for example, than ensuring that a tubular device is properly anchored inan afferent vessel and in an efferent vessel.

In some embodiments in which embolic material was previously inserted inan aneurysm but has herniated, certain devices described herein may beused as a “rescue device” to push the herniated material back into theaneurysm and to act as a scaffolding to inhibit or prevent furtherherniation or prolapse of the embolic material. In certain suchembodiments, deployment of such devices may advantageously avoidtraversal of the junction comprising the herniated material by wires ora catheter (e.g., there is no need to traverse wires or a catheter pastthe junction into an efferent vessel for positioning of the device as isgenerally needed to position tubular devices such as the devices 42, 44illustrated in FIGS. 4B and 4C), which may cause the herniated materialto become tangled and/or dislodged and which may cause rupture of theaneurysm.

Although this invention has been disclosed in the context of certainembodiments and examples, it will be understood by those skilled in theart that the invention extends beyond the specifically disclosedembodiments to other alternative embodiments and/or uses of theinvention and obvious modifications and equivalents thereof. Inaddition, while several variations of the embodiments of the inventionhave been shown and described in detail, other modifications, which arewithin the scope of this invention, will be readily apparent to those ofskill in the art based upon this disclosure. It is also contemplatedthat various combinations or sub-combinations of the specific featuresand aspects of the embodiments may be made and still fall within thescope of the invention. It should be understood that various featuresand aspects of the disclosed embodiments can be combined with, orsubstituted for, one another in order to form varying modes of theembodiments of the disclosed invention. Thus, it is intended that thescope of the invention herein disclosed should not be limited by theparticular embodiments described above.

What is claimed is:
 1. A vascular remodeling device comprising: aplurality of polymer filaments; wherein proximal ends of the pluralityof polymer filaments are coupled together by a bioabsorbable coupling ata proximal end of the device; wherein the coupling is configured tobioabsorb more quickly than does the plurality of polymer filaments;wherein the proximal ends of the plurality of polymer filaments areconfigured to be released from the coupling after bioabsorption of thecoupling.
 2. The device of claim 1, wherein at least some of the polymerfilaments comprise polyglycolic acid, polylactic acid,poly(lactic-co-glycolic acid), poly-epsilon-caprolactone, ornaturally-derived bioabsorbable polymers.
 3. The device of claim 1,wherein a first group of the polymer filaments comprise a first polymerhaving a first rate of bioabsorption and a second group of the polymerfilaments comprise a second polymer different than the first polymer,the second polymer having a second rate of bioabsorption different thatthe first rate of bioabsorption.
 4. The device of claim 1, wherein thedevice is generally football-shaped, the proximal end of the deviceextending outwardly and a distal end extending outwardly.
 5. The deviceof claim 1, wherein the device is generally pumpkin-shaped, the proximalend of the device extending outwardly and a distal end extendinginwardly.
 6. The device of claim 1, wherein a first porosity distallyincreases between the second end and an approximate midpoint and whereina second porosity distally decreases between the midpoint and the firstend.
 7. The device of claim 1, wherein the filaments are longitudinallyangled at the distal end.
 8. The device of claim 1, wherein theplurality of filaments comprises between about 6 filaments and about 12filaments.
 9. The device of claim 1, wherein the plurality of polymerfilaments are configured to extend towards an afferent vessel afterbioabsorption of the coupling.
 10. A vascular remodeling devicecomprising: a first end; a second end substantially opposite to thefirst end; and a plurality of polymer filaments extending between thefirst end and the second end and coupled at the first end and the secondend, wherein a first group of the polymer filaments comprises a firstpolymer having a first rate of bioabsorption and a second group of thepolymer filaments comprises a second polymer different than the firstpolymer, the second polymer having a second rate of bioabsorptiondifferent than the first rate of bioabsorption.
 11. The device of claim10, wherein at least some of the polymer filaments comprise polyglycolicacid, polylactic acid, poly(lactic-co-glycolic acid),poly-epsilon-caprolactone, or naturally-derived bioabsorbable polymers.12. The device of claim 10, wherein the device is generallyfootball-shaped, the first end extending outwardly and the second endextending outwardly.
 13. The device of claim 10, wherein the device isgenerally pumpkin-shaped, the first end extending outwardly and thesecond end extending inwardly.
 14. The device of claim 10, wherein afirst porosity distally increases between the second end and anapproximate midpoint and wherein a second porosity distally decreasesbetween the midpoint and the first end.
 15. The device of claim 10,wherein the filaments are longitudinally angled at the second end. 16.The device of claim 10, wherein the plurality of filaments comprisesbetween about 6 filaments and about 12 filaments.
 17. The device ofclaim 10, wherein a proximal end of the device comprises a bioabsorbablecoupling.
 18. The device of claim 17, wherein the coupling is configuredto bioabsorb more quickly than the plurality of polymer filaments. 19.The device of claim 18, wherein the plurality of polymer filaments areconfigured to be released from the coupling after bioabsorption of thecoupling.
 20. The device of claim 18, wherein the plurality of polymerfilaments are configured to extend towards an afferent vessel afterbioabsorption of the coupling.